Co-owned Pat. Nos. 4,581,026, 4,626,250, and 4,932,948 disclose male external catheters intended for use with urinary drainage systems. Each such catheter is in the form of a sheath having a cylindrical body section, an intermediate neck section, and a reduced drainage tube section, with the entire catheter being formed of a soft elastic material such as latex or silicone rubber. In addition, the catheters disclosed in each of these patents have tubular elongated inner sleeves of soft elastic material designed to fit over the glans of a wearer's penis. Such a sleeve is intended to make sealing contact with the glans and is maintained in stretched condition over the glans by adhesive means adhering the cylindrical section to the penile shaft.
As shown in these patents, the tubular sleeves are relatively long, so as to cover as much of the glans as possible, and terminate in small distal openings so that urine may be discharged into the intermediate neck portions of the sheaths. For sealing effectiveness, it has been considered important to insure that the thin elastic sleeves are stretched over the glans and are maintained in such stretched condition when the catheters are worn. That requires the caregiver or the patient (if a catheter is self-applied) to hold the penis in position as the sleeve is stretched over the glans. While devices have been developed to make the task easier (see, for example, the applicator of co-owned Pat. No. 4,589,874), it is still necessary for the user to use both hands in the application of such a catheter, one for unrolling the sheath over the penis and the other for holding the penis, with the sleeve in stretched condition over the glans, at least at the commencement of that operation.
While an adhesively-attached catheter with an inner sleeve operates effectively if it is applied carefully with the sleeve stretched over the glans, instances have occurred where nurses (or other caregivers) have failed to perform such procedures completely, or with sufficient patience and care, because they are concerned about possible discomfort or injury to the patient, or are rushing to perform other healthcare duties, or simply because they find themselves uncomfortable making such direct and extended contact with the limp penis of an incontinent patient. If such an external catheter is improperly or incompletely applied, it may cause considerable patient discomfort and produce other serious consequences such as rendering the device ineffective or inoperative and causing leakage of urine when the drainage system is in use.
Other problems may also arise. If the stretched inner sleeve is to cover the glans, it is important that it be relatively long and that its distal opening be small. However, such a device obviously will fail to operate properly if the small distal opening of the stretched sleeve is not in register with the urethral opening of the patient, so care must be taken to assure that proper alignment exists. Also, in fitting such a sheath upon a patient, it is important that the sleeve be stretched, but not stretched excessively, because excessive stretching might cause the distal end of the sleeve to be positioned near the backside of the glans, or even behind the glans, applying a clearly undesirable constrictive force on the patient.
Recent developments in catheter-applying techniques involve the use of catheters that are similar to those described above but may or may not supplied or applied in rolled form and may or may not have inner sleeves. Reference may be had to co-owned Pat. Nos. 5,423,784, 5,336,211, 4,586,974, 4,540,409, and Des. No. 358,882. In each, a catheter is supported by an open-ended applicator tube with the neck and drainage tube portions of the catheter located within the tube and the cylindrical portion of the catheter reverted or turned backwardly over the outside of the tube. Such a system generally allows the user to apply a catheter to a patient without gripping the penis between the fingers, but some gripping may still be necessary if the catheter has an inner sleeve that should be stretched over the glans during application. In such a case, the ease of application may be decreased rather than increased because operation of the applicator tube in releasing and applying a catheter is itself a two-handed operation, making it difficult for the user to also hold the penis and stretch the sleeve over the glans.
An important aspect of this invention therefore lies in the discovery that the advantages of sleeve-equipped catheter may be realized without encountering the difficulties indicated above if such a sleeve is shortened, its opening is greatly enlarged, and it is positioned so that it may make sealing contact with the penile shaft rather than the glans. Unlike the inner sleeves of the catheters disclosed in the aforementioned patents, the sleeve of the present catheter must be relatively short, taking the form of a narrow annular flap, and its opening must be relatively large. Specifically, the opening must be large enough so that the annular flap slides easily over the glans (or the foreskin covering the glans in an uncircumcised patient) and will sealingly engage the penile shaft or the proximal portion of the glans (or foreskin) immediately adjacent the shaft. The flap should be dimensioned so that its opening has a diameter in the general range of 75 to 92% of the inside diameter of the cylindrical portion of the sheath, with the preferred range being 78 to 89% and the optimum range being about 81 to 87%. The length of the flap depends partly on the size of the catheter but, in general, the flap should have a length within the range of about 0.25 to 0.65 inches and should not in any case exceed 35% of the length of the sheath's intermediate section. A flap length of 0.5 inches has been found particularly effective for adult-size catheters, whereas 0.3 inches has been found suitable for a pediatric-size catheter.
Other features, objects and advantages will become apparent from the specification and drawings.